Battery Capacity Calculator

Understand Battery Capacity

Battery capacity tells you how much energy a battery can store. Manufacturers typically list this as watt-hours (Wh) or amp-hours (Ah), and understanding both helps you compare batteries across different devices.

When to Use Each Unit

Watt-hours (Wh) is the most useful for comparing batteries regardless of voltage. A 500Wh e-bike battery and a 500Wh scooter battery store the same total energy, even if they run at different voltages.

Amp-hours (Ah) tells you how long a battery can deliver current. This matters when you know the voltage and want to understand how long you can drive/ride. Most e-bike and scooter batteries are rated in Ah.

Kilowatt-hours (kWh) is standard for electric cars. 1 kWh equals 1,000Wh.

Milliamp-hours (mAh) is used for small electronics like phones and power banks. A typical phone battery is 3,000-5,000 mAh.

Why Voltage Matters

A battery’s voltage affects its power output. Higher voltage batteries can deliver more power at the same current, which is why performance scooters often use 60V or 72V systems instead of 48V.

However, higher voltage doesn’t mean more range – that depends on total watt-hours. A 48V 20Ah battery (960Wh) stores more energy than a 72V 10Ah battery (720Wh).